Engineering Pilot 1

September 21, 2017

Our latest task was returning to China for our first engineering pilot (EP1). The goal of the first pilot was to evaluate the initial state of the plastics from tooling and also take a first look at the assembly process. This was the first time we had all the real plastic parts, gearboxes, and PCBs and it’s a big step toward completing the project. From here on out there is a lot of detail work to make sure everything functions properly and that Mousr continues to be reliable as he zooms around and crashes.

Overall, we were quite happy with the first run of plastics. You can see us checking out the tooling and first shots in the pictures below.

Fai and Gary with one of the injection tools, Doom with the charger tool loaded on an injection machine, checking out first shots, Mousr parts ready for assembly.

There are still some marks we need to clean up, but it was a great start for the initial plastics. While extensive simulation is done of how plastic flows in the mold, uneven cooling can cause various kinds of marks. There is also additional polishing that needs to be done to reach the clear glossy finish we want on the charger.

If you look closely at the pictures you can see common problems with initial plastics such as scuff marks and sink marks. These issues will be improved for the next pilot.

Mousr is quick and nimble and we're really happy with how he is driving on a variety of floor surfaces. This is the first time we had a Mousr prototype in our target size and weight and watching him zip around and tumble was really exciting.

https://vimeo.com/234023343PW: mousr

We decided to include an insert metal piece that will allow you to remove and reinstall the wheels many times. This means Mousr should never be disabled by long hair wrapping around the axle.

Analyzing the first shot gearboxes. The insert piece for improving wheel replacement.

As we’ve mentioned in previous updates, one of the biggest cosmetic challenges is making Mousr’s sensors work within the aesthetic design. This challenge has extended to color as well. One issue we ran into with the plastic in EP1 was that when using lighter colors, infrared light was leaking through the plastic walls. We tried some additives that are specifically designed to reduce infrared transmission, but we could not reduce the leakage enough to make the proximity sensing reliable. The result is that we had to move to a fairly dark grey in order to make the sensors functional. You can see the initial grey color (Mousr’s body) in the image below as well as the color we ended up with (Mousr’s head). We may be able to figure out a way to use lighter colors in the future, but for now, the main color of Mousr will be fairly dark.

If you’ve ever taken apart a commercial product, you know that getting it back together isn’t so easy. Our goal is to make the assembly process for Mousr as easy and reliable as possible. Currently, the head portion of Mousr is really easy to assemble, and the only details to work out are the sensors and infrared light leakage. The body, on the other hand, is quite tricky. Not only is there significantly less space than in the head, but there is a lot of hand soldering and wire routing needed to connect the battery and motors. Routing the wires is particularly difficult given the limited amount of space, and would have been impossible if we hadn’t already reduced the complexity by moving to the flexible PCB design we showed you in the past.

In order to refine the assembly issues, we will begin our second pilot in just over a week. We are currently making adjustments to the tooling and some minor PCB changes in order to enable easier assembly. We are also looking at designing some assembly fixtures to make the assembly process easier. We hope that by the end of this second pilot we will have narrowed the concerns enough so we can confidently start our final pilot and ship out to beta testers. We’ll keep you updated on the progress.

The EP1 crew.

Before we go, we’d like to introduce some new members of the Petronics family, Taco and Burrito and their proud papa Dennis. Dennis has been working on Mousr firmware for the past year and you can check out a video of Taco and Burrito playing at his house with the latest Mousr prototype below.